Tips For Installing Felt Paper On Your Roof

8 July 2015

Marvin Simmons

Felt paper is commonly used as a moisture barrier underneath metal or asphalt roofing. This is important, because moisture under your main roofing can damage the sub-roofing otherwise. You may have also heard of felt paper referred to as tar paper in some roofing circles. If you're putting a new roof on your house you'll want to add a layer of this material. While you can install it on your own, it's best to make this a two-person project. That way, one of you can roll it out and hold it in place while the other staples it to secure it. Here's a look at what you need to know to tackle the project today.

Gathering What You Need

Before you start working on the roof, you need to make sure you have all of the supplies you'll need. For example, you should have two extension ladders available so that you and your assistant can easily reach the roof. You'll also need the felt paper, a utility knife, a staple gun and roofing staples. Your roofing contractor can tell you how many rolls of felt paper you'll need based on the square footage of your roof.

Getting Ready to Work

You won't need to do any special preparation to the roof before you apply the felt paper. This serves as a base under the shingles, so as soon as the sub-roof is ready for shingles, you can apply the felt paper. And, since the felt paper rolls are fairly uniform in width, you don't even have to do any measurements before you apply it.

Installing the Paper

Place one ladder at the corner where you want to start working. Place the other ladder about five feet or so away along the same exterior wall. Once the ladders are stable, you and your assistant will need to climb them to get the paper where it needs to go.

Lay the paper on the roof and push the roll toward your helper so that it unrolls in that direction. He or she should hold the roll while you line up the edge of the felt paper with the roof's edge. Make sure that it's lined up both horizontally and vertically. The edges of the paper should overlap the drip edge on the roof by about a half-inch or so.

Use the staple gun to secure the paper, putting a staple about every five or six inches along the length of the strip. Use as many staples as needed to ensure that it's secure. Move the ladder from the corner to a position several feet down the wall on the opposite side of the roll. Repeat the process to continue applying the strip of felt paper along the length of the roof.

Repeat this process along the entire length of the roof. When you reach the edge, cut the felt paper with a razor blade or utility knife. Then, shift the roll of felt paper up slightly so you can work your way back the other way, applying a second layer above the first. The second layer should overlap the first by about an inch or two. Do this until the entire roof is covered in felt paper. Once finished, you can install your roofing shingles.